Steam generating apparatus



March 24, i936. A E, DURAM STEAM GENERATING APPARATUS 2 sheets-sheet 1 Filed OGt. l0, 1934 OO OO oooo ocoooo oo O 003D ovo on Mwoo oo o@ 0G INVENTOR.

ATTGRNEY.

March 24, 1936. A E, DURAM ,2,034,717

STEAM GENERAT'ING APPARATUS Filed Oct. lO, 1954 l 2 Sheets-Sheet 2 INVENTOR.

rzw 6). ,Datum p OM@ ATTORNEY.

Patented Mar. 24, 1936 UNITED sr STEAM GENERATING APPARATUS corporation of Illinois Application October 10, 1934, Serial No. 747,764

7 Claims.

This invention relates to steam generating apparatus and particularly to apparatus of this kind of relatively large size and high steam generating capacity. Certain features of the imvention are directed to the water walls of the furnace which are intended to reduce the temperature of the furnace in order to keep the same below the fusing temperature of the slag or noncombustible ingredients of the fuel which is being burned in the furnace.

Heretofore in furnaces of this type it has been standard practice to water cool the rear and side walls, and in cases of high heat release, the front Wall, which has operated in a reasonably satisfactory manner up to a furnace width of approximately fifteen feet. In furnaces of greater width than this where two or more burners are employed to generate the necessarysteam requirements, it has been found that the radiant absorption to the outside wall cooling tubes has been reasonably satisfactory to reduce the temperature of the rising ash particles below a plastic temperature in the portions of the furnace Y adjacent 'to such outer walls. However, in the center of the furnace between the burners where the burning fuel has a tendency to cloud the radiant effect of such outer wall tubes it has been found that the furnace temperature rises to a considerable extent above the balance of the furnace, creating a plastic condition of the ash which accumulates rapidly upon the lower tube bank of the boiler, diminishing the gas passages to such an extent as to prohibit normal operation. In order to reduce this higher temperature in the center of the furnace attempts have been made to install single rows of vertical water tubes between the burner zones. In such conditions it has been found that due to the excessive radiant heat absorbed from both sides of the single row of tubes, the evaporation in such vertical rows has been extremely excessive even to the point of lowering the water content in the tubes to such an extent as to overheat the tubes and cause failure.- In order to overcome such a condition 45 I propose to install a double row of tubes in such formation as to cause one row toshield the other from the radiant heat of the opposite Zone and thereby create an operating condition having a degree of radiant absorption in the center or partition wall more nearly to that of the outside wall and reduce the possibility of excessive generation in the tubes of the center or partition wall. o

The objects of this invention as above indicated are to provide an improved steam generat- (Cl. 122-235) Y n acter having means for access to various por- 5" tions thereof for construction, inspection and cleaning purposes; and to provide such other improvements in construction and advantages in operation as will appear more fully from the following description. l0

vIn the accompanying drawings illustrating this invention,

Figure 1 is a vertical sectional view taken approximately on the line l-I of Figure 4;

Figure 2 is a detail of one of the headers with 2 pipes connected therewith;

Figure 3 is a detail of the center wall supporting means; and

Figure 4 is a vertical sectional view taken on the line 4 4 of Figure 1. 20

It will be understood that in these drawings parts are shown Y diagrammatically and other parts may be omitted, sufficient being illustrated so that the invention will be readily understood 7 by those familiar with the art. 25

As shown particularly in Figure 1, the furnace or combustion chamber 5 is shown with a rear water wall 6 and side water walls 1 and 8 and if desired may be provided with a front water wall, which however is not shown, this being more or less standard construction. The tubes of the rear water wall yare connected at the top with a header 9 and at the bottom with a header III. The header 9 is connected to the boiler drum Il in any suitable or well-known manner as by means of risers l2. The return from the drum II to the lower header III may also be arranged in any desired manner, as for instance in the arrangement shown, a transverse header I3 is connected to the drum by means of a plurality of pipes I4. Dcwncomer or return pipes I5 extend downwardly from the ends of the header I3 and are connected to the header Ill by a plurality of pipes I6 as shown. Y

The tubes of the waterwall 1 are connected at 45 the top with a header I'I and at the bottom with with a header I8 and the tubes of the water wall 8 are connected in a similar manner at the top with a header I9 and at the bottom with a header 20. The headers I'I and I9 may be connected 50 with the drum I I in any standard or well-known manner as by means of pipes 2| and 22. The headers I8 and 20 are connected respectively with the return pipes I5 by means of pipes 23 and 24 which enter the ends of short headers 25 which 55 are directly connected to the lower ends of the pipes |5 as shown in Figure 4.

The boiler proper includes upper and lower banks of tubes 26 and 21 which are separated vertically for purposes which will be presently explained. The tubes of the upper bank 26 are connected with headers 26 and 29 and the tubes of the lower bank with headers 35 and 3|. The high end headers 28` and 30 are connected together in the usual manner and are connected to the drum I by tubes 32. The low end headers 29 and 3| are connected together in the usual manner and are connected with the drum by` return pipes 33.

In the form shown the furnace is provided with two openings 34 and 35 for the burners :(not` shown) and the combustion chamber is divided into two compartments by. my improved center.

or partition wall, although of course any desired number of such walls may be used to dividethe furnace into as many sections as desired.

The center or partition wallA includes two sets of tubes 36 and 31, the tubesof each set being of suflicient size and suitably spaced to' reduce the temperatureV of the adjacent portions of the furnace to the desired degree. Asshown, the tubes of thewalls36 andA 31`are'arranged sufciently closeto .make substantially. two water" walls adapted to divide the furnace into two separate chambers. However, if desired, refractory material 38 .may be inserted in the space between these walls in order to entirely separate the adjacent. portions of the furnace.

The upper ends of the tubes of `the water'wall 36are connectedwith a header 39, and the lower ends 'are connected with a header 43. The upper ends of the tubes of the water wall 31 are like- Wise connected with a header 4| which' is arranged adjacent .to the header 39 and the lower ends of these tubes are connected .with a header. 42. it will' be understood that the two rows of 'tubes of thewater wall may.v if desired be .connected with a single header at the top.. The headers 39 and 4| are connected respectively tothe drum I through suitable riser tubes 43'. and 44.` The upper ends'of the tubes. 43and 44 are arranged adjacent to each other and extend. througha suitable opening in the .upper bank 26'of boiler tubes.' The lower ends of the tubes 43'.and 44A however are spread apart or separated to pro'- videan access passageway 45 above the headers 39. and .4| in order to provide access to the hand hole covers' 46 along the top of the headers, for cleaning and repair. rlhis passageway maybe enclosed by means of side plates or walls 41 and is provided at the end with .necessary entrance doors 43. ofa pipe 49 with the return pipe 23' and the header 42 is connected by a pipe 59 with the return' pipe 24 in order to complete the circuits ofthe water through the center or partition walls 36 and 31."

that theydiverge andform a passageway or opening 5|* between the headers. The center walls 36-and` 31 are carried by a longitudinal .beam 52 While I have shown two headers 39 and 4|" The header 49 is connected by means which is supported in any suitable manner, the tubes being provided with supporting ns or lugs 53 which are welded thereto and which rest on the beam.

The spreading of the tubes of the center water walls provides sloping side walls for the ash discharge openings 54 and 55 which extend longitudinally of the furnace instead of transversely as in the usual construction. The opposite sloping side walls of. these ash discharges are formed by bending in the lower ends of the tubes of the side walls 1 and 8, thus providing V-shaped discharge openings across the bottom of the furnace. The Atubes of the water walls 1 and B are also provided with lugs or fins 56 and 51 which are carried on beams58'andv 59which extend longitudinally an automatic sluicing system as indicated. atll'l or a standard'ash pocket 6| for hand disposal .as also vshown in Figure 1.1 The sides of the ash discharge portion of the furnace, as well as other. parts of the apparatus, may be provided with 'any standard formof refractory or insulated type of setting as maybe required.

In the particular'embodiment ofrmy invention shown, the upper and lower banks of boiler tubes have'been separatedY a suflicient distance Vto per.

mit the installation of a superheater .62', which may be suitably connected to the druml in any desired manner." However, Where a superheater is not'required less distance may be .providedbetween 'the' upper and lower banksor the boiler;

tubesu may be combined ina single bank and merelysuicient .space left atthe center for. the

headers'39 and 4| and the other parts connected therewith. and Afor the access passageway..

The operation of my improved apparatuswilff bereadily apparent from the above description taken in connection'with the drawings. When.

heat is supplied' tothe two sections of the furnace by means'of.suitable burners, the center water.. wall 3|`willl`cooperate with the water. wall 1 inl.

ordertof keep the temperature inthe corresponding section reduced to the desired amount. In a like manner the water wall.38 will cooperate with the side water wall 8 to-control thetemperature in the other section." It' will ybe noted that each. of the centerv water walls will substantially ab-L.-

sorb its proportion of the radiant heat from its individual section and will protect theother wall...

from being vinjuriously affected bythe radiant. heat from the burner in such section. The.cir. culation through the boiler and other features of-: operation are sufficiently obvious so that further..

description does not appear necessary.

Any invention or subject matter herein shown or .described but not claimed is not intendedto be.

dedicated to thepublic, such matter being shown.

described and claimed in.my copendingr divisional application for Steam generators, Serial Number 53,880, filed December 11, 1935.

It will be noted that while I have shown a pre-.- ferred form of my invention it may be embodied:

in various different types of furnaces and different kinds of boilers of either thecross drum type as shown or the long drum type, or other types to.. which it maybe applicable, and therefore I do, not wish to be limited to the particular construe--l tion herein shown and described except as set forth in the following claims, .in which I claim:

1. In an apparatus of the character set forth,

- the combination of a boiler having upper and lower banks of tubes and having a drum connected therewith, of a furnace having side water walls and having a partition formed of two adjacent water walls extending upwardly through the lower bank of tubes and terminating between the banks, headers for the upper and lower ends of said water walls, means connecting the headers with the drum and an enclosed access passageway above the upper headers to provide access thereto.

2. The combination with a boiler of the inclined horizontal tube type having a bank of tubes and having a drum connected with said tubes, of a furnace, means for dividing the furnace into zones, comprising two series of tubes arranged adjacent to each other, the tubes of one series being adapted to shield the tubes of the adjacent series, headers for the lower ends of each of the series, headers for the upper ends of each of the series located above the lower tubes of the boilers, pipes leading from said last named headers to the drum, the upper portions of the pipes being arranged adjacent to each other, and the lower portions of the pipes of the adjacent headers being spaced apart to provide a passageway and a lining for enclosing said passageway.

3. A furnace having a partition comprising two tubular water walls arranged adjacent to each other, headers connecting the lower ends of the tubes of the respective walls, the lower portions of the tubes being spread apart to provide access to the headers.

4. A furnace including a combustion chamber having side water walls each formed of a series of tubes and having a central partition formed of two adjacent water walls which divides the chamber into sections, the lower portions of the tubes of the water walls in each section of the furnace being converged to provide longitudinal ash discharges, the space between the lower portions of the partition water walls also providing access to the headers at the lower ends of said walls.

5. A furnace having a combustion chamber divided into a plurality of sections for combustion Zones, each section having tubular water walls on either side thereof and means for supporting each of said walls at a predetermined distance from the lower end thereof whereby the expansion and contraction of all of the walls below the supports will be substantially the same.

6. A furnace comprising a substantially-rectangular combustion chamber divided into two longitudinal sections to provide separate combustion zones, tubular water walls on either side of each section, the lower ends of the tubes of each section converging and forming an ash discharge passageway, and means for supporting all of said tubes at substantially the same distance from the lower ends thereof.

7. In a steam generator, the combination of a boiler having upper and lower banks of tubes, a drum operatively connected with said tubes, a series of vertical tubes extending longitudinally of the boiler with their upper ends above the lower bank and their lower ends projecting downwardly to the bottom of the furnace, a header connecting the lower ends of the tubes of said series, a second header connecting the upper ends of said series, means for operatively connecting said headers with the drum, a second series of tubes arranged adjacent to the first series and substantially parallel thereto, the tubes of the second series being co-extensive with the tubes of the rst series, a header for the lower ends of the tubes of the second series, a header for the upper ends of the tubes of the second series arranged in juxtaposition to the upper header of the rst series and means for operatively connecting the headers of the second series with the drum.

ARTHUR E. DURAM. 

